Unconfirmed reports claim the ex-girlfriend of North Korean leader Kim Jong Un was executed by firing squad along with 11 others, after the group allegedly made and sold a sex tape.

Hyon Song Wol, a singer in North Korea’s famed Unhasu Orchestra, was killed by machine gun along with 11 other members of the orchestra and the Wangjaesan Light Music Band, another popular state-run music group in North Korea, according to a report in The Chosun Ilbo, South Korea’s largest daily newspaper.

The report, which cites an anonymous source in China, says the group was arrested Aug. 17 for filming and selling a pornographic video featuring themselves. The clip reportedly found its way across the border to China. Their families were forced to watch the execution, which took place three days later, and were then sent to the country’s notorious prison camps, the source said.

Hyon was a famous performer whose fame peaked around 2005 with the popular song “Excellent Horse-Like Lady.” She is said to have dated Kim in the early 2000’s, after the young leader returned from boarding school in Switzerland. But she disappeared from the public eye around 2006, near the time Kim Jong Il began grooming his son to be Supreme Leader. (Kim Jong Il reportedly disapproved of the relationship and ordered Hyon to leave the orchestra to keep her away from his son.)